This invention relates to methods for inhibiting angiogenesis in a mammal by the local administration of an activated hyaluronic acid composition to the site where the anti-angiogenesis effect is desired. The anti-angiogenesis method of this invention can be used to control or inhibit solid tumor growth in cancer patients, to modulate wound healing, and to prevent or reduce inflammation.
Vasculogenesis is a necessary process in the establishment of embryonic tissue whereby endothelial cells are born from progenitor cell types. In contrast, angiogenesis is a process wherein new capillaries sprout from existing vessels. Thus, angiogenesis is necessary for the establishment and development of tumor tissue, as well as the control of certain inflammatory conditions. Angiogenesis is also known to play an integral role in wound healing by allowing tissue generation and remodeling. The inhibition of angiogenesis can be a useful tool for the control of wound healing, inflammation and solid tumor growth.
Angiogenesis-dependent diseases are those diseases which require or induce vascular growth. Such diseases represent a significant portion of all diseases for which medical treatment is sought, and include cancers and inflammatory arthritis.
Standard approaches for the treatment and management of cancer involve the use of surgical procedures to excise the tumor, followed by the use of chemotherapeutic drugs and/or radiation treatment to prevent a reoccurrence of the cancer. The chemotherapeutic drugs, such as cisplatin and methotrexate, are typically introduced directly into the patient""s blood stream and carried to the site of the tumor. There is now evidence, however, that tumors actually compress their blood supply, making it difficult for the drug to reach the target cancer cells. In order to reach the cancer cells, the drugs must cross the blood-vessel wall and the interstitial spaces within the tumor. An alternative approach is to develop drugs which will inhibit the growth of blood vessels within the tumor.
U.S. Pat. No. 4,771,042 discloses steroid compositions which are useful for inhibiting angiogenesis. These compositions are administered intramuscularly, intravenously or orally, and are useful for treating various traumas, cancer and infertility.
U.S. Pat. No. 5,001,116 describes the inhibition of angiogenesis by the co-administration of heparin and steroids. The patent discloses that neither the steroids nor heparin alone have any anti-angiogenic activity, and it is the combination of the two which is unexpectedly effective for this purpose. The routes of administration are parenteral or oral, and the compositions are disclosed as being particularly useful for tumor regression or to prevent metastasis.
Hyaluronic acid (xe2x80x9cHAxe2x80x9d) is a naturally occurring mucopolysaccharide found, for example, in synovial fluid, in vitreous humor, in blood vessel walls and the umbilical cord, and in other connective tissues. The polysaccharide consists of alternating N-acetyl-D-glucosamine and D-glucuronic acid residues joined by alternating xcex21-3 glucuronidic and xcex21-4 glucosaminidic bonds, so that the repeating unit is -(1xe2x86x924)-xcex2-D-GlcA-(1xe2x86x923)-xcex2-D-GlcNAc-. In water, hyaluronic acid dissolves to form a highly viscous fluid. The molecular weight of hyaluronic acid isolated from natural sources generally falls within the range of 5xc3x97104 up to 1xc3x97107 daltons.
Hyaluronic acid, in chemically modified (xe2x80x9cderivatizedxe2x80x9d) or crosslinked form, is useful as a surgical aid to prevent adhesions or accretions of body tissues during the post-operative period. The derivatized or crosslinked HA gel or film is injected or inserted into the locus between the tissues that are to be kept separate to inhibit their mutual adhesion. Chemically modified or crosslinked HA can also be useful for controlled release drug delivery. See U.S. Pat. Nos. 4,937,270 and 5,017,229 which disclose derivatized versions of HA, or HA in combination with other polyanionic polysaccharides such as carboxymethylcellulose, which can be prepared by reacting the HA with a carbodiimide. U.S. Pat. No. 4,582,865, and pending U.S. application Ser. No. 09/503,544, filed Feb. 14, 2000, each describe the reaction of hyaluronic acid with divinyl sulfone, and the use of these products in medical applications.
A derivatized version of HA and carboxymethylcellulose (xe2x80x9cCMCxe2x80x9d), in combination, is available commercially as Seprafilm(trademark) membranes and films from the Genzyme Corporation. CMC is an anionic polysaccharide and a derivatized form of cellulose in which the glucosidic hydroxyl groups have been carboxymethylated, thereby rendering the polymer water soluble. This derivative of HA and CMC can be prepared by mixing HA with CMC and an activating agent to form a water insoluble precipitate. The precipitate is cast into a thin film membrane, which can be implanted into the peritoneal cavity or other sites to prevent the formation of post-operative adhesions.
I. Danishefsky et al., Carbohydrate Res., Vol. 16, pages 199-205, 1971, describe modifying a mucopolysaccharide by converting the carboxyl groups of the mucopolysaccharide into substituted amides by reacting the mucopolysaccharide with an amino acid ester in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (xe2x80x9cEDCxe2x80x9d) in aqueous solution. Danishefsky et al. react glycine methyl ester with a variety of polysaccharides, including HA. The resulting products are water soluble; that is, they rapidly disperse in water or in an aqueous environment such as is encountered between body tissues.
U.S. Pat. No. 5,847,002 describes a method for inhibiting, controlling or regressing angiogenesis by administering to a subject a non-steroidal anti-inflammatory agent (xe2x80x9cNSAIDxe2x80x9d) and hyaluronic acid (xe2x80x9cHAxe2x80x9d). The function of the NSAID is to decrease the production of inflammatory mediators, many of which are pro-angiogenic, thereby inhibiting granuloma formation. The patent states that the NSAID and HA act synergistically as an angiostatic agent.
U.S. Pat. No. 5,902,795 discloses the use of hyaluronan oligosaccharides and antibodies to hyaluronan binding proteins to treat tumors or other diseases which can be linked to angiogenesis. The compositions of this patent block the hyaluronan binding protein on the cell surface during tumor cell and endothelial cell migration, and during capillary-like tubule formation.
U.S. Pat. No. 6,022,866 describes the use of solutions of hyaluronic acid to prevent arterial restinosis. The hyaluronic acid solution is administered to a patient to prevent the narrowing of the tubular walls of an artery after being traumatized, such as the narrowing which can occur following a balloon angioplasty procedure.
It will be appreciated that there is a need for an improved anti-angiogenesis formulation and therapeutic treatments which use such formulations.
In general terms, the present invention features a method for inhibiting angiogenesis in a mammal by the local administration of an activated hyaluronic acid composition to the site where the anti-angiogenesis result is desired. The anti-angiogenesis method of this invention can be used to control or inhibit solid tumor growth in cancer patients, to modulate wound healing, and to prevent or reduce inflammation and inflammatory diseases.
In one aspect, the activated polyanionic polysaccharide is formed by reacting the polyanionic polysaccharide with a carbodiimide in an aqueous medium under suitable reaction conditions. The preferred pH for carrying out the reaction is 3.5 to 8.0. The preferred concentration for the polyanionic polysaccharide is from about 0.005 to 0.1M, more preferably from about 0.01 to 0.02M. The molar ratio of the polyanionic polysaccharide to activating agent is preferably at least 1:1, and more preferably about 1:4. The preferred carbodiimide is 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide or 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide methiodide.
In a further aspect, the crosslinked polyanionic polysaccharide compositions are prepared by reacting the polyanionic polysaccharide with a suitable crosslinking agent, such as divinyl sulfone, in a solvent under suitable reaction conditions.
In another aspect, the anti-angiogenesis compositions of this invention are used in a therapeutic method for the treatment of solid cancerous tumors and surrounding tissue. The compositions of this invention can be used alone, or in combination with other anti-angiogenic compositions, such as steroids, which can be administered to the site of the cancerous tumor. The pharmaceutical preparations can also include other pharmaceutically active substances dispersed throughout, making the preparations useful as drug delivery vehicles. Suitable pharmaceutically active substances include proteins, such as growth factors, soluble receptors and enzymes, drugs, antibodies, biopolymers, and biologically compatible synthetic polymers.
In a further aspect, this invention encompasses a method for the treatment of non-tumorigenic, angiogenesis-dependent diseases by the administration of the present compositions to the site of the inflammation to inhibit the formation of new blood vessels. Preferred angiogenesis-dependent diseases which may be treated by the compositions of this invention include, for instance, inflammatory arthritis, such as rheumatoid arthritis.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any method and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned hereunder, including published patent applications, and issued or granted patents, are incorporated by reference in their entirety. Unless mentioned otherwise, the techniques employed or contemplated herein are standard methodologies well known to one of ordinary skill in the art. The materials, methods and examples are illustrative only and not intended to be limiting.
Other features and advantages of the invention will be apparent from the following description of the preferred embodiments, and from the claims.